Micellar Ratiometric Fluorescent Blood pH Probe Based on Triplet-Sensitized Upconversion and Energy-Transfer Behaviors
Chun Zhang, Lin Li, Lei Xu, Changqing Ye, Pengju Han, Meng Wang, Renjie Liu, Shuoran Chen, Xiaomei Wang, Yanlin Song
Abstract
The measurement of pH is greatly significant in monitoring physiological and biochemical states. In this work, a novel micellar ratiometric fluorescent probe featuring sophisticated energy-transfer (ET) behaviors with p-nitrophenol (PNP) as the energy acceptor and a triplet–triplet annihilation upconversion (TTA-UC) system as the energy donor was designed. The pH-induced molecular configuration of PNP determined the process for the transfer of energy from TTA-UC to PNP. The introduction of the TTA-UC system enabled probe excitation under a long wavelength and afforded a ratiometric signal for pH detection with excellent reliability over diverse interfering factors. This TTA-UC/ET pH probe demonstrated a high sensitivity to hydronium below nanomolar concentrations and an excellent anti-interference ability in serum samples, which provided a novel significant strategy for rapid and accurate detection of blood pH in vitro.